diff --git a/gstreamer-editing-services/Gir.toml b/gstreamer-editing-services/Gir.toml
index 459eb2d00..f020e81a2 100644
--- a/gstreamer-editing-services/Gir.toml
+++ b/gstreamer-editing-services/Gir.toml
@@ -59,11 +59,9 @@ generate = [
     "GES.BaseTransitionClip",
     "GES.BaseXmlFormatter",
     "GES.ChildrenControlMode",
-    "GES.ClipAsset",
     "GES.CommandLineFormatter",
     "GES.Edge",
     "GES.EditMode",
-    "GES.EffectAsset",
     "GES.EffectClip",
     "GES.Error",
     "GES.ExtractableCheckId",
@@ -83,7 +81,6 @@ generate = [
     "GES.PipelineFlags",
     "GES.Source",
     "GES.SourceClip",
-    "GES.SourceClipAsset",
     "GES.TestClip",
     "GES.TextHAlign",
     "GES.TextOverlay",
@@ -91,12 +88,9 @@ generate = [
     "GES.TextVAlign",
     "GES.TitleClip",
     "GES.TitleSource",
-    "GES.TrackElementAsset",
     "GES.TrackType",
     "GES.Transition",
     "GES.TransitionClip",
-    "GES.UriClipAsset",
-    "GES.UriSourceAsset",
     "GES.VideoSource",
     "GES.VideoStandardTransitionType",
     "GES.VideoTestPattern",
@@ -110,6 +104,7 @@ generate = [
 [[object]]
 name = "GES.Asset"
 status = "generate"
+concurrency = "send+sync"
     [[object.function]]
     name = "set_proxy"
         [object.function.return]
@@ -161,6 +156,11 @@ status = "generate"
         [object.function.return]
         nullable_return_is_error = "Failed to split clip"
 
+[[object]]
+name = "GES.ClipAsset"
+status = "generate"
+concurrency = "send+sync"
+
 [[object]]
 name = "GES.Container"
 status = "generate"
@@ -192,6 +192,11 @@ status = "generate"
         [object.function.return]
         nullable_return_is_error = "Failed to create effect from description"
 
+[[object]]
+name = "GES.EffectAsset"
+status = "generate"
+concurrency = "send+sync"
+
 [[object]]
 name = "GES.Extractable"
 status = "generate"
@@ -260,6 +265,11 @@ status = "generate"
         [object.function.return]
         bool_return_is_error = "Failed to remove asset"
 
+[[object]]
+name = "GES.SourceClipAsset"
+status = "generate"
+concurrency = "send+sync"
+
 [[object]]
 name = "GES.Timeline"
 status = "generate"
@@ -466,6 +476,11 @@ status = "generate"
         name = "value"
         const = true
 
+[[object]]
+name = "GES.TrackElementAsset"
+status = "generate"
+concurrency = "send+sync"
+
 [[object]]
 name = "GES.UriClip"
 status = "generate"
@@ -474,6 +489,16 @@ status = "generate"
         [object.function.return]
         nullable_return_is_error = "Failed to create Uri clip from Uri"
 
+[[object]]
+name = "GES.UriClipAsset"
+status = "generate"
+concurrency = "send+sync"
+
+[[object]]
+name = "GES.UriSourceAsset"
+status = "generate"
+concurrency = "send+sync"
+
 [[object]]
 name = "Gst.Buffer"
 status = "manual"
diff --git a/gstreamer-editing-services/src/auto/asset.rs b/gstreamer-editing-services/src/auto/asset.rs
index 3375cf00e..6e5222435 100644
--- a/gstreamer-editing-services/src/auto/asset.rs
+++ b/gstreamer-editing-services/src/auto/asset.rs
@@ -126,6 +126,9 @@ impl Asset {
     }
 }
 
+unsafe impl Send for Asset {}
+unsafe impl Sync for Asset {}
+
 pub trait AssetExt: 'static {
     #[doc(alias = "ges_asset_extract")]
     fn extract(&self) -> Result<Extractable, glib::Error>;
@@ -162,10 +165,13 @@ pub trait AssetExt: 'static {
     fn unproxy(&self, proxy: &impl IsA<Asset>) -> Result<(), glib::error::BoolError>;
 
     #[doc(alias = "proxy")]
-    fn connect_proxy_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;
+    fn connect_proxy_notify<F: Fn(&Self) + Send + Sync + 'static>(&self, f: F) -> SignalHandlerId;
 
     #[doc(alias = "proxy-target")]
-    fn connect_proxy_target_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;
+    fn connect_proxy_target_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId;
 }
 
 impl<O: IsA<Asset>> AssetExt for O {
@@ -241,8 +247,11 @@ impl<O: IsA<Asset>> AssetExt for O {
         }
     }
 
-    fn connect_proxy_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
-        unsafe extern "C" fn notify_proxy_trampoline<P: IsA<Asset>, F: Fn(&P) + 'static>(
+    fn connect_proxy_notify<F: Fn(&Self) + Send + Sync + 'static>(&self, f: F) -> SignalHandlerId {
+        unsafe extern "C" fn notify_proxy_trampoline<
+            P: IsA<Asset>,
+            F: Fn(&P) + Send + Sync + 'static,
+        >(
             this: *mut ffi::GESAsset,
             _param_spec: glib::ffi::gpointer,
             f: glib::ffi::gpointer,
@@ -263,8 +272,14 @@ impl<O: IsA<Asset>> AssetExt for O {
         }
     }
 
-    fn connect_proxy_target_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
-        unsafe extern "C" fn notify_proxy_target_trampoline<P: IsA<Asset>, F: Fn(&P) + 'static>(
+    fn connect_proxy_target_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId {
+        unsafe extern "C" fn notify_proxy_target_trampoline<
+            P: IsA<Asset>,
+            F: Fn(&P) + Send + Sync + 'static,
+        >(
             this: *mut ffi::GESAsset,
             _param_spec: glib::ffi::gpointer,
             f: glib::ffi::gpointer,
diff --git a/gstreamer-editing-services/src/auto/clip_asset.rs b/gstreamer-editing-services/src/auto/clip_asset.rs
index 2ca53161e..5133aa4a2 100644
--- a/gstreamer-editing-services/src/auto/clip_asset.rs
+++ b/gstreamer-editing-services/src/auto/clip_asset.rs
@@ -30,6 +30,9 @@ impl ClipAsset {
     pub const NONE: Option<&'static ClipAsset> = None;
 }
 
+unsafe impl Send for ClipAsset {}
+unsafe impl Sync for ClipAsset {}
+
 pub trait ClipAssetExt: 'static {
     #[cfg(feature = "v1_18")]
     #[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
@@ -51,7 +54,10 @@ pub trait ClipAssetExt: 'static {
     fn set_supported_formats(&self, supportedformats: TrackType);
 
     #[doc(alias = "supported-formats")]
-    fn connect_supported_formats_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;
+    fn connect_supported_formats_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId;
 }
 
 impl<O: IsA<ClipAsset>> ClipAssetExt for O {
@@ -102,10 +108,13 @@ impl<O: IsA<ClipAsset>> ClipAssetExt for O {
         }
     }
 
-    fn connect_supported_formats_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
+    fn connect_supported_formats_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId {
         unsafe extern "C" fn notify_supported_formats_trampoline<
             P: IsA<ClipAsset>,
-            F: Fn(&P) + 'static,
+            F: Fn(&P) + Send + Sync + 'static,
         >(
             this: *mut ffi::GESClipAsset,
             _param_spec: glib::ffi::gpointer,
diff --git a/gstreamer-editing-services/src/auto/effect_asset.rs b/gstreamer-editing-services/src/auto/effect_asset.rs
index 0e0a82a3d..64bf33d7d 100644
--- a/gstreamer-editing-services/src/auto/effect_asset.rs
+++ b/gstreamer-editing-services/src/auto/effect_asset.rs
@@ -17,3 +17,6 @@ glib::wrapper! {
 impl EffectAsset {
     pub const NONE: Option<&'static EffectAsset> = None;
 }
+
+unsafe impl Send for EffectAsset {}
+unsafe impl Sync for EffectAsset {}
diff --git a/gstreamer-editing-services/src/auto/source_clip_asset.rs b/gstreamer-editing-services/src/auto/source_clip_asset.rs
index b89c64482..be20926be 100644
--- a/gstreamer-editing-services/src/auto/source_clip_asset.rs
+++ b/gstreamer-editing-services/src/auto/source_clip_asset.rs
@@ -17,3 +17,6 @@ glib::wrapper! {
 impl SourceClipAsset {
     pub const NONE: Option<&'static SourceClipAsset> = None;
 }
+
+unsafe impl Send for SourceClipAsset {}
+unsafe impl Sync for SourceClipAsset {}
diff --git a/gstreamer-editing-services/src/auto/track_element_asset.rs b/gstreamer-editing-services/src/auto/track_element_asset.rs
index e7b8403d8..ba19b428c 100644
--- a/gstreamer-editing-services/src/auto/track_element_asset.rs
+++ b/gstreamer-editing-services/src/auto/track_element_asset.rs
@@ -27,6 +27,9 @@ impl TrackElementAsset {
     pub const NONE: Option<&'static TrackElementAsset> = None;
 }
 
+unsafe impl Send for TrackElementAsset {}
+unsafe impl Sync for TrackElementAsset {}
+
 pub trait TrackElementAssetExt: 'static {
     #[cfg(feature = "v1_18")]
     #[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
@@ -42,7 +45,10 @@ pub trait TrackElementAssetExt: 'static {
     fn set_track_type(&self, type_: TrackType);
 
     #[doc(alias = "track-type")]
-    fn connect_track_type_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;
+    fn connect_track_type_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId;
 }
 
 impl<O: IsA<TrackElementAsset>> TrackElementAssetExt for O {
@@ -82,10 +88,13 @@ impl<O: IsA<TrackElementAsset>> TrackElementAssetExt for O {
         }
     }
 
-    fn connect_track_type_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
+    fn connect_track_type_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId {
         unsafe extern "C" fn notify_track_type_trampoline<
             P: IsA<TrackElementAsset>,
-            F: Fn(&P) + 'static,
+            F: Fn(&P) + Send + Sync + 'static,
         >(
             this: *mut ffi::GESTrackElementAsset,
             _param_spec: glib::ffi::gpointer,
diff --git a/gstreamer-editing-services/src/auto/uri_clip_asset.rs b/gstreamer-editing-services/src/auto/uri_clip_asset.rs
index f29bcc54e..36df8e4d1 100644
--- a/gstreamer-editing-services/src/auto/uri_clip_asset.rs
+++ b/gstreamer-editing-services/src/auto/uri_clip_asset.rs
@@ -65,6 +65,9 @@ impl UriClipAsset {
     }
 }
 
+unsafe impl Send for UriClipAsset {}
+unsafe impl Sync for UriClipAsset {}
+
 pub trait UriClipAssetExt: 'static {
     #[doc(alias = "ges_uri_clip_asset_get_duration")]
     #[doc(alias = "get_duration")]
@@ -97,12 +100,18 @@ pub trait UriClipAssetExt: 'static {
     fn is_nested_timeline(&self) -> bool;
 
     #[doc(alias = "duration")]
-    fn connect_duration_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;
+    fn connect_duration_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId;
 
     #[cfg(feature = "v1_18")]
     #[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
     #[doc(alias = "is-nested-timeline")]
-    fn connect_is_nested_timeline_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId;
+    fn connect_is_nested_timeline_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId;
 }
 
 impl<O: IsA<UriClipAsset>> UriClipAssetExt for O {
@@ -160,10 +169,13 @@ impl<O: IsA<UriClipAsset>> UriClipAssetExt for O {
         glib::ObjectExt::property(self.as_ref(), "is-nested-timeline")
     }
 
-    fn connect_duration_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
+    fn connect_duration_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId {
         unsafe extern "C" fn notify_duration_trampoline<
             P: IsA<UriClipAsset>,
-            F: Fn(&P) + 'static,
+            F: Fn(&P) + Send + Sync + 'static,
         >(
             this: *mut ffi::GESUriClipAsset,
             _param_spec: glib::ffi::gpointer,
@@ -187,10 +199,13 @@ impl<O: IsA<UriClipAsset>> UriClipAssetExt for O {
 
     #[cfg(feature = "v1_18")]
     #[cfg_attr(docsrs, doc(cfg(feature = "v1_18")))]
-    fn connect_is_nested_timeline_notify<F: Fn(&Self) + 'static>(&self, f: F) -> SignalHandlerId {
+    fn connect_is_nested_timeline_notify<F: Fn(&Self) + Send + Sync + 'static>(
+        &self,
+        f: F,
+    ) -> SignalHandlerId {
         unsafe extern "C" fn notify_is_nested_timeline_trampoline<
             P: IsA<UriClipAsset>,
-            F: Fn(&P) + 'static,
+            F: Fn(&P) + Send + Sync + 'static,
         >(
             this: *mut ffi::GESUriClipAsset,
             _param_spec: glib::ffi::gpointer,
diff --git a/gstreamer-editing-services/src/auto/uri_source_asset.rs b/gstreamer-editing-services/src/auto/uri_source_asset.rs
index 8f8ad0f16..2a29bee46 100644
--- a/gstreamer-editing-services/src/auto/uri_source_asset.rs
+++ b/gstreamer-editing-services/src/auto/uri_source_asset.rs
@@ -19,6 +19,9 @@ impl UriSourceAsset {
     pub const NONE: Option<&'static UriSourceAsset> = None;
 }
 
+unsafe impl Send for UriSourceAsset {}
+unsafe impl Sync for UriSourceAsset {}
+
 pub trait UriSourceAssetExt: 'static {
     #[doc(alias = "ges_uri_source_asset_get_filesource_asset")]
     #[doc(alias = "get_filesource_asset")]
diff --git a/gstreamer-editing-services/src/formatter.rs b/gstreamer-editing-services/src/formatter.rs
index 4f53f1ed5..f8cdca8b0 100644
--- a/gstreamer-editing-services/src/formatter.rs
+++ b/gstreamer-editing-services/src/formatter.rs
@@ -67,7 +67,7 @@ impl<O: IsA<crate::Formatter>> FormatterExtManual for O {
                 caps.to_glib_none().0,
                 version,
                 rank.into_glib(),
-            );
+            )
         }
     }
 }